1. Field of the Invention
The present invention relates to articulated support assemblies that can be retrofitted to existing desks or horizontal surfaces, the assemblies being designed to permit the user to adjust the position of a workstation or keyboard to the most desirable location and store the keyboard or workstation under the desk when it is inactive, thus maximizing work space use.
2. Description of the Prior Art
Devices designed to support keyboards or workstations relative to a desk edge are widely available. Most of these devices maintain a set elevation and merely extend from below the desk where they are stored and the support is attached and are designed primarily for use while the operator of the keyboard is seated at the workstation. These devices have tended to increase their intrusion into the knee-space of the user to obtain a greater degree of motility. In creating motility, they have also generally required more depth of the under desk surface to retract the mechanisms that were designed to create range of motion. The devices were not primarily designed to allow the user to sit or stand at his/her workstation.
U.S. Pat. No. 5,211,367 to Musculus discloses an articulating arm connected to the center and front edge of the keyboard support surface and is capable of accommodating most adjustment conditions from a seated position. The greatest intrusion into the users work area is the knee space that requires straddling the single arm to keyboard interface. In addition, this central arm support method does not create the degree of horizontal stability at the distal areas of the keyboard support. This device also requires large depths under the desk surface for mounting the device. Due to the depth required, many desks that have a knee apron may not be suitable for this assembly, the assembly being based on three adjustment points. In addition, the assembly is not suitable with the operator in a standing position.
U.S. Pat. No. 5,823,487 to Kirchhoff et al discloses a device that uses two support arms that allow the device greater stability at the lateral distal surfaces of the keyboard support and has a total of three pivot points. Two pivot points are under the desk at the distal ends of the keyboard support surface and are arrested by gears with latching cogs. The third pivot point is a generally U shaped torsion bar that the keyboard tray rotates above and around on a horizontal axis. This rotation is arrested by a clutch assembly below the keyboard that allows virtually any angle of keyboard adjustment. It is limited, however, in that the method of connection from the generally U shaped torsion bar that extends from the desk to the keyboard tray uses valuable space in the height of the keyboard tray itself. This does not allow the user to place the keyboard close to a lap position while seated. This device also requires more under desk space than is available in desks with knee aprons. In addition, the production of the device is expensive as it has gears and clutch assemblies that are labor intensive.
U.S. Pat. No. 5,791,263 to Watt et al discloses a work surface that supports an auxiliary device such as a keyboard and is adjustable for vertical movement relative to the work surface or desk it is mounted to. It consists of two sets of parallel arm subassemblies that are horizontally spaced by approximately 80% of the moveable work surface. The generally vertical parallel arms are linked by a horizontal torsion tube for stability on the horizontal plane. This assembly includes a release mechanism that permits arresting the platform at any point within its range of motion, the range of motion being from approximately 4 inches below the desk surface to approximately 6 inches thereabove. Persons of minimal stature can stand or sit while interfacing with the keyboard. However, the '263 system does not have wrist angle adjustment of the keyboard support surface relative to the angle of the users wrist. In addition, the system mechanisms are placed in a manner that is invasive of the knee user space. Further, the '263 system does not retract horizontally under the desk surface, an important requirement of most conventional systems.
Other prior art assemblies are generally less adaptable for ergonomic user adjustment as they are typically less adjustable for height and angle of the keyboard/workstation. Thus, an improved keyboard or workstation support is desired that will address these problems and create the freedom to sit or stand at the workstation.